PLS HELP ME ASAPPP!!!!​

Answer:

x = 6 ± 5[tex]\sqrt{3}[/tex]

Step-by-step explanation:

Given

x² - 12x = 39

Using the method of completing the square

add ( half the coefficient of the x- term)² to both sides

x² + 2(- 6)x + 36 = 39 + 36

(x - 6)² = 75 ( take the square root of both sides )

x - 6 = ± [tex]\sqrt{75}[/tex] = ± 5[tex]\sqrt{3}[/tex] ( add 6 to both sides )

x = 6 ± 5[tex]\sqrt{3}[/tex] ← solutions in exact form

Answer:

x = 6 ± 5* OR 6 - 5*

Step-by-step explanation:

In decimal form it would be either 14.66025403... or -2.66025403

Hope this helps!

Answer:

40%

Step-by-step explanation:

Because there are 5 rectangle total, we can dive 100% into 5 parts.

Each part is then 20%, there are 2 shaded rectangles thus the answer is 40%.

Answer:

A) It will get to a temperature of 125°F at 9:19 PM

B) It will get to a temperature of 150°F at 9:16 PM

C) as time passes temperature approaches the initial temperature of 450°F

Step-by-step explanation:

We are given;

Initial temperature; T_i = 450°F

Room temperature; T_r = 70°F

From Newton's law of cooling, temperature after time (t) is given as;

T(t) = T_r + (T_i - T_r)e^(-kt)

Where k is cooling rate and t is time after the initial temperature.

Now, we are told that After 5​ minutes, the temperature is 300°F.

Thus;

300 = 70 + (450 - 70)e^(-5k)

300 - 70 = 380e^(-5k)

230/380 = e^(-5k)

e^(-5k) = 0.6053

-5k = In 0.6053

-5k = -0.502

k = 0.502/5

k = 0.1004 /min

A) Thus, at temperature of 125°F, we can find the time from;

125 = 70 + (450 - 70)e^(-0.1004t)

125 - 70 = 380e^(-0.1004t)

55/380 = e^(-0.1004t)

In (55/380) = -0.1004t

-0.1004t = -1.9328

t = 1.9328/0.1018

t ≈ 19 minutes

Thus, it will get to a temperature of 125°F at 9:19 PM

B) Thus, at temperature of 150°F, we can find the time from;

150 = 70 + (450 - 70)e^(-0.1004t)

150 - 70 = 380e^(-0.1004t)

80/380 = e^(-0.1004t)

In (80/380) = -0.1004t

-0.1004t = -1.5581

t = 1.5581/0.1004

t ≈ 16 minutes.

Thus, it will get to a temperature of 150°F at 9:16 PM

C) As time passes which means as it approaches to infinity, it means that e^(-kt) gets to 1.

Thus,we have;

T(t) = T_r + (T_i - T_r)

T_r will cancel out to give;

T(t) = T_i

Thus, as time passes temperature approaches the initial temperature of 450°F

Answer:

We accept the null hypothesis, that is, that the population mean is not different from 0.7.

Step-by-step explanation:

A brochure claims that the average maximum height a certain type of plant is 0.7 m.

This means that the null hypothesis is:

[tex]H_{0}: \mu = 0.7[/tex]

A gardener suspects that this estimate is not accurate locally due to soil conditions.

Hypothesis test to determine whether the population mean is different from 0.7m, which means that the alternate hypothesis is:

[tex]H_{a}: \mu \neq 0.7[/tex]

The test statistic is:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.

0.7 is tested at the null hypothesis:

This means that [tex]\mu = 0.7[/tex]

A random sample of 43 plants is taken. The mean height of the plants in the sample is 0.65m.

This means, respectively, that [tex]n = 43, X = 0.65[/tex]

Assume that the population standard deviation is 0.2 m.

This means that [tex]\sigma = 0.2[/tex]

Value of the test statistic:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

[tex]z = \frac{0.65 - 0.7}{\frac{0.2}{\sqrt{43}}}[/tex]

[tex]z = -1.64[/tex]

Pvalue of the test:

Since we are testing that the mean is different of a value, and z is negative, the pvalue of the test is 2 multiplied by the pvalue of z = -1.64

z = -1.64 has a pvalue of 0.0505

2*0.0505 = 0.101

Using a 1% level of significance, perform a hypothesis test to determine whether the population mean is different from 0.7m.

0.101 > 0.01, which means that we accept the null hypothesis, that is, that the population mean is not different from 0.7.

uhhh...p=3.4 is already simplified.

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hope it helps???

Answer:

A,C,D,F

Step-by-step explanation:

Answer:

r = 6

r = 9

Step-by-step explanation:

Answer is in the file below

tinyurl.com/wpazsebu

Answer:

Step-by-step explanation:

It is easy to see that (-2, 0) and (0, -4) are points on the line.

gradient = (difference of y-coordinates)/(difference of x-coordinates) = (0-(-4))/(-2-0) = 4/(-2) =  -2

I will do 9 only. You can do 11.

Question 9

sin(60) = x/8

sin(60)(8) = x

4•sqrt{3} = x

x^2 + y^2 = 8^2

(4•sqrt{3})^2 + y^2 = 64

16(3) + y^2 = 64

48 + y^2 = 64

y^2 = 64 - 48

y^2 = 16

sqrt{y^2} = sqrt{16}

y = 4

Do 11 the same way.

Answer:

81 Degrees

Step-by-step explanation:

The triangles are congruent and a triangle is 180 degrees total. So, 57+42=99. 180-99=81

So the answer is 81 degrees.

Answer:

36

Step-by-step explanation:

Answer:

Part A:

I would multiply the length, width, and depth of the pool to find the volume of it. That would be how much water can fit inside. 25 ft x 15 ft x 10 ft = 3750 ft

Part B:

a. 3750 ft

Answer:

Expression that represents the sale price of the wedding dress is  

Solution:

Given that, the dress is on sale for 35 % off the regular price

Let the regular price of dress be "w"

To find: Expression that represents the sale price of the wedding dress

Let "s" be the sale price of wedding dress

Sale price = Regular price - discount price

Discount price is given as:

Discount price = 35 % of regular price

Discount price = 35 % of w  

Thus discount price = 0.35w

Expression for the sale price of the wedding dress:

Sale price = Regular price - discount price

s = w - 0.35

s = 0.65

s= 0.65

Thus expression that represents the sale price of the wedding dress is

s=0.56

Answer:

Step-by-step explanation:

Answer: C. Daphne's test score is 2.50 standard deviations above the average test score of students in the course.

Step-by-step explanation: That's what Z-score is

Answer:

the cost of each is  £10 and  £8 respectively

Step-by-step explanation:

Let us assume the cost of per DVD be x

And the cost of per CD be y

Now as per the question

The following equations should be made

3x + 4y = £62.00

4x + 3y = £64.00

Now multiply by 4 in equation 1 and 3 in equation 2

12x + 16y = £248

12x + 9y = £192

7y =  £56

y =  £8

Now put the value of y in any of the above equation

3x + 4( £8) =  £62

3x +  £32 =  £62

3x = 30

x =  £10

Hence, the cost of each is  £10 and  £8 respectively

Answer:

Not to conclude that the drug is safe, when, in fact, it is safe.

Step-by-step explanation:

A type ii error is an error that occurs in a hypothesis testing when a person goes ahead to accept a null hypothesis when it is actually false and should be rejected.

To continue, here are the hypothesis:

H0: the drug is unsafe

H1: drug is safe.

A type ii error was committed here because H0, which is the null was accepted and it was concluded that the drug was unsafe, When in fact it should have been rejected. The conclusion should have been that the drug was safe.

Answer:

10=10

Step-by-step explanation:

_1(12)+14=2(12)+2

3.

Answer:

a) The point estimate of the population proportion of adults who lack confidence they will be able to afford health insurance in the future us 0.58.

b) The margin of error is of 0.03.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.

[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

In which

z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].

Point estimate:

The point estimate is [tex]\pi[/tex].

Margin of error:

The margin of error is:

[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

(a) What is the point estimate of the population proportion of adults who lack confidence they will be able to afford health insurance in the future.

579 out of 1007 adults. So

[tex]\pi = \frac{579}{1007} = 0.575[/tex]

Rounding to two decimal places, 0.58

The point estimate of the population proportion of adults who lack confidence they will be able to afford health insurance in the future us 0.58.

(b) At 90% confidence, what is the margin of error

90% confidence level

So [tex]\alpha = 0.1[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.1}{2} = 0.95[/tex], so [tex]Z = 1.645[/tex].

The margin of error is:

[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

[tex]M = 1.645\sqrt{\frac{0.58*0.42}{1007}}[/tex]

[tex]M = 0.03[/tex]

The margin of error is of 0.03.

Answer:

she should set up a budget on how much she makes

Step-by-step explanation:

Answer:

37.7 inches

Step-by-step explanation:

Formula of circumference:

[tex]2\pi r[/tex]

r = radius

In the current case,

radius is 6 inches

Hence,

circumference=

[tex]2*\pi *6\\= 12\pi\\= 37.6991118431[/tex]

≅ 37.7 inches

Feel free to mark it as brainliest

Answer:

5x - ((2x-1)÷2) = 5-----(1)

(1) multiply by 2;

2 *(5x - ((2x-1)÷2) = 5)

10x - (2x-1) = 10

10x - 2x + 1  = 10

8x + 1 =10

8x = 10-1

x=9 /8

Step-by-step explanation:

Answer:

x = 9/8

Step-by-step explanation:

5x - ((2x - 1) ÷ 2) = 5​

2 × (5x - ((2x - 1) ÷ 2) = 5

10x - (2x-1) = 10

10x - 2x + 1  = 10

8x + 1 = 10

8x + 1 - 1 = 10 - 1

8x = 10 - 1

8x = 9

8x ÷ 8 = 9 ÷ 8

x = 9 ÷ 8

x = 9/8 or 1 and 1/8